Carburetor high speed jet cleaning
- Thread starter germaic
- Start date
Assuming that it is jetted properly,It sounds like you have a buildup of sediment from the tank in the bottom of the float bowl. If it ran fine previously, then this is probably what the problem is if it looses power in the upper throttle positions like high speed.
The high speed jet is at the lowest point in the float bowl so it is the first affected when you have sediment in the float bowl.
Look between the cylinders from the horn side of the bike and you'll see a brass screw in the base of the float bowl. Open it up a few turns and allow a few ounces of fuel to drain out which will come out in front of the rear tire. The petcock should be open when you do this and if you have a vacuum petcock you'll have to apply vacuum to open it being the motor isn't running when you do this.
Take it for a ride and when you come back, do it again.
The high speed jet is at the lowest point in the float bowl so it is the first affected when you have sediment in the float bowl.
Look between the cylinders from the horn side of the bike and you'll see a brass screw in the base of the float bowl. Open it up a few turns and allow a few ounces of fuel to drain out which will come out in front of the rear tire. The petcock should be open when you do this and if you have a vacuum petcock you'll have to apply vacuum to open it being the motor isn't running when you do this.
Take it for a ride and when you come back, do it again.
What about EFI models...
I dont know anything about Harley EFI but the Honda VTX1800 has Advanced high-pressure programmed fuel injection (PGM-FI) features 42mm-diameter throttle bodies delivering air to two specially designed Denso(r) 50-psi high-pressure fuel injectors. Fuel is delivered through 12 nozzle holes in each injector, producing an atomized fuel mixture that is highly combustible for maximum efficiency and power.
So how does Honda with EFI get around this. The last thing you want is to clog up the injectors or is this really an issue with any EFI system
I dont know anything about Harley EFI but the Honda VTX1800 has Advanced high-pressure programmed fuel injection (PGM-FI) features 42mm-diameter throttle bodies delivering air to two specially designed Denso(r) 50-psi high-pressure fuel injectors. Fuel is delivered through 12 nozzle holes in each injector, producing an atomized fuel mixture that is highly combustible for maximum efficiency and power.
So how does Honda with EFI get around this. The last thing you want is to clog up the injectors or is this really an issue with any EFI system
Like Hobbit said it only stops the larges particles. The sediment is so fine that it goes right through that screen in the tank.
Can't comment on the Honda's, but the Harley FI bikes have a fuel filter inside the tank in the line that takes most everything out of the fuel because of the orifices in the injectors being so small.
You can see the filter here closest to the box coming from the pump.
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Hello Glider,
I only tried to clean he carb last week and I did not find the screw you showed on the picture. My sportster is a 1986/87. What shall I do?
Remove the carb and dismantle it to clean the main jet and the the little tank?
Thanks a lot for help. I have no access without taking the carb out.
I only tried to clean he carb last week and I did not find the screw you showed on the picture. My sportster is a 1986/87. What shall I do?
Remove the carb and dismantle it to clean the main jet and the the little tank?
Thanks a lot for help. I have no access without taking the carb out.